An artificial cardiac pacemaker is an electronic device that functions as the SA (sino-atrial) node which normally initiates the impulse for contraction of the heart muscle.

A temporary pacemaker is an “artificial” pacemaker that takes the place of or overrides a faulty SA node. The device is inserted by threading a lead or wire through a vein into the right ventricle of the patient’s heart. At the other end, outside of the patient’s body, the wire is attached to a power source which stimulates the heart to contract. 

Temporary pacemakers are often used in emergency situations to keep a person’s heart beat stable until a permanent pacemaker can be inserted. It also may be used after a heart attack to keep the heart rhythm normal until the extent of tissue damage can be established.